This section explains how to interpret group trends and periodic trends in ....
Periodic Trends Review. 1. Finish the following sentences with, “increases,” or ...
Unit 10: The Periodic Table (Chapter 6)
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What Do We Have in Common?
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DIRECTIONS: Locate the symbols on the PT on the front of this page. Determine what they have in common and complete the table (i.e. metal, nonmetal, state of matter, group number, family name, etc.)
Symbol
Common Characteristics
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Name ____________________________________________________ Period ___________________
THE PERIODIC TABLE SECTION 6.1 ORGANIZING THE ELEMENTS (pages 155–160)
This section describes the development of the periodic table and explains the periodic law. It also describes the classification of elements into metals, nonmetals, and metalloids. Searching For An Organizing Principle (page 155) 1. How many elements had been identified by the year 1700? ________________ 2. What caused the rate of discovery to increase after 1700? _____________________________________ _________________________________________________________________________________________ 3. What did chemists use to sort elements into groups? __________________________________________ _______________________________________________________________________________________ Mendeleev’s Periodic Table (page 156) 4. Who was Dmitri Mendeleev? _______________________________________________________________ 5. What property did Mendeleev use to organize the elements into a periodic table? _________________________________________________________________________________________ 6. True/false? Mendeleev used his PT to predict the properties of undiscovered elements.__________ The Periodic Law (page 157) 7. How are the elements arranged in the modern periodic table? _________________________________ 8. True or false? The periodic law states that when elements are arranged in order of increasing atomic number, there is a periodic repetition of physical and chemical properties. ______________________ Metals, Nonmetals, and Metalloids (pages 158–160) 9. Explain the color coding of the squares in the periodic table in Figure 6.5. _______________________ ________________________________________________________________________________________ 10. Which property below is not a general property of metals. a. ductile
b. poor conductor of heat
c. malleable
d. high luster
11. True/False. The variation in properties among metals is greater than the variation in properties among nonmetals. __________________ 12. Under some conditions, a metalloid may behave like a _____________________ . Under other conditions, a metalloid may behave like a _____________________ . 5
SECTION 6.2 CLASSIFYING THE ELEMENTS (pages 161–167)
This section explains why you can infer the properties of an element based on the properties of other elements in the periodic table. It also describes the use of electron configurations to classify elements. 5. Classify each as a (an) alkali metal, alkaline earth metal, halogen, or noble gas. a. sodium ______________________
e. xenon
______________________
b. chlorine ______________________
f. potassium
______________________
c. calcium ______________________
g. magnesium ______________________
d. fluorine ______________________ 6. How many electrons are in the highest occupied energy level? a. Group 3A __________
b. Group 1A __________
c. Group 8A __________ it
8. Circle the letter of the elements found in the p block. a. Groups 1A and 2A and helium b. Groups 3A, 4A, 5A, 6A, 7A, and 8A except for helium c. transition metals d. inner transition metals Match the category of elements with an element from that category. _______________ 9. Noble gases
a. gallium
_______________ 10. Representative elements
b. nobelium
_______________ 11. Transition metals
c. argon
_______________ 12. Inner transition metals
d. vanadium
13. Use Figure 6.12 on page 166. Write the electron configurations for the following elements. a. magnesium
______________________________________
b. cobalt
______________________________________
c.
______________________________________
sulfur
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Historical Figures in Chemistry
Dmitri Mendeleev and the Periodic Table
The arrangement of elements in the Using the modern periodic table, modern periodic table is clearly connected look at the following pairs of to atomic structure. However, the concept elements: Ar and K, Te and I, and of the periodic table has been known for Co and Ni. In each case, the first more than 100 years, and it was developed element has the greater atomic long before our more recent knowledge weight. Arranging them in order of of electron configurations. The history of increasing atomic weight would the ideas of chemical periodicity is filled place a very reactive metal in the with interesting people, and one of the column with the very inert elements. most important was the Russian chemist The fault lies in Mendeleev’s Dmitri Mendeleev (1834 - 1910). assumption that properties of In the 19th century many chemists tried elements are periodic functions of to find relationships between atomic their weight. weights and the properties of the elements. H.G.J. Moseley, a young scientist These efforts largely failed because atomic working with Ernest Rutherford, A young Dmitri Mendeleev weights were not known for all elements, found that the wavelengths of x-rays emitted by an and many measured values were inaccurate. element are related in a precise way to the atomic However, at a conference in 1860 in Germany, number of the element. He quickly realized that Stanislao Cannizzaro (1826 - 1910) described his other atomic properties may be related to atomic method for determining accurate and unambiguous number and not, as Mendeleev had proposed, to atomic weights, and this began to set things right. atomic weight. Indeed, if the elements are arranged Mendeleev was at the conference and doubtless by atomic number, the defects in Mendeleev’s table head Cannizzaro’s paper. It led him to become the are corrected. It was therefore Moseley who founder of the concept of chemical periodicity. discovered the law of chemical periodicity, which Mendeleev’s ideas on periodicity began in the late states that the properties of elements are periodic 1860’s with his work on a book on inorganic functions of their atomic numbers. chemistry. To help organize the material for his book, After Mendeleev published his work on chemical he had a file of note cards, one for each element. On periodicity, he did little else with the subject. Instead, each card he wrote the atomic weight of the he went on to other interests. In 1876 he visited the element, then known more accurately owing to US to study the fledgling oil industry and was Cannizzaro’s work, and some properties of the impressed by the industry but not the country. element. When he arranged these cards in order of America, he thought, was not interested in science, increasing atomic weight, he saw there was a and even worse, carried on the worst features of repetition of properties every eight or eighteen European civilization. elements. Thus was born Mendeleev’s periodic table. One final note: All pictures of Mendeleev show More than 100 years later, we recognize Mendeleev’s him with long hair. He made it a rule to get his hair work as a milestone, because he had the genius to cut only once a year, in the spring, whether he realize that (a) there were many elements to be needed it or not. discovered and (b) the characteristics of an element could be predicted from its atomic weight and its position on the table. Mendeleev’s table led directly to the discovery of several elements within a few years after he published the table. In spite of Mendeleev’s great achievement, problems arose when new elements were discovered and more accurate atomic weights were determined.
Dmitri Mendeleev in 1904 7
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Properties of the groups on the periodic table Circle the correct answer 1. Mendeleev noticed that properties of elements appeared at regular intervals when the elements were arranged by a. atomic mass. c. reactivity. b. number of protons. d. atomic number. 2. Elements in the same group or column on the periodic table can be expected to have similar a. atomic masses. c. atomic numbers. b. number of neutrons. d. properties. 3. The radioactive elements with atomic numbers from 89-102 on the periodic table are referred to as the a. noble gases. c. lanthanides. b. actinides. d. halogens. 4. Argon, krypton, and xenon are all a. noble gases. b. actinides.
c. alkaline earth metals. d. transition elements.
5. Elements on the right side of the periodic table tend to exhibit properties of a. nonmetals. c. metals. b. metalloids. d. gases. 6. Elements in which the d sublevel is being filled exhibit properties of a. nonmetals. c. metals. b. metalloids. d. gases. 7. Since the column one elements are highly reactive, these alkali metals exist as ______ in nature. a. elements. c. compounds. b. solutions. d. gases. 8. Compared to the alkali metals, the alkaline earth metals a. are less reactive. c. are less dense. b. have lower melting points. d. combine more readily with nonmetals. 9. What group of elements reacts vigorously with water? a. halogens c. noble gases b. alkali metals d. transition metals 10. Tungsten and copper are elements that belong to the a. halogens. c. noble gases. b. alkali metals. d. transition metals. 11. The most reactive nonmetals are the a. halogens. b. oxygen family of elements.
c. noble gases. d. 1s electron filling elements.
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Fill in the blank with the correct word or phrase. 12. The Law _________________________________________________________________, also called the Periodic Law, states that “the physical and chemical properties of elements are periodic functions of their atomic numbers.” 13. The work of _________________________________ led to the periodic table based on atomic number. 14. Neutral atoms with an s2p5 configuration are called _____________________________________. 15. Elements that border the “staircase” on the periodic table are called _____________________________. true or false: 16. Elements in the same row have similar electron configurations.
_________________
17. Elements in the same column exist in the same phase at room temperature.
_________________
18. Elements in the same family must all be metals or nonmetals.
_________________
19. Elements in the same period have their valence electrons in the same energy level. ________________ 20. Elements in the same group have similar chemical properties.
_________________
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SECTION 6.3 PERIODIC TRENDS (pages 170–178)
This section explains how to interpret group trends and periodic trends in atomic size, ionization energy, ionic size, and electronegativity. Trends in Atomic Size (pages 170–171) 1. True/false? The radius of an atom can be measured directly. ______________________ 2. What are the atomic radii for the following molecules? molecule
Hydrogen
atomic radius
_____________
Oxygen
_____________
Nitrogen
_____________
Chlorine
_____________
3. What is the general trend in atomic size within a group? Within a period? _______________________ ________________________________________________________________________________________ 4. What are the two variables that affect atomic size within a group? a. _____________________________________
b. _____________________________________
5. For each pair of elements, pick the element with the largest atom. a. Helium & argon _____________________
b. Potassium & argon _____________________
6. What is an ion? _________________________________________________________________________ 7. How are ions formed? ___________________________________________________________________ 8. An ion with a (+) charge is called a(n) ___________; an ion with a (-) charge is called a(n) __________. 9. Complete the following table about anions and cations. Anions
Cations
Charge Metal/Nonmetal -/+ Trends in Ionization Energy (page 173 - 175) 10. ______________________ is the energy required to overcome the attraction of protons in the nucleus and remove an electron from a gaseous atom. 11. Why does ionization energy tend to decrease from top to bottom within a group? ________________ _________________________________________________________________________________________ 12. Why does ionization energy tend to increase as you move across a period? ______________________ _________________________________________________________________________________________ 11
Trends in Ionic Size (page 176) 14. Metallic elements tend to ______________________ electrons and form ______________________ ions. Nonmetallic elements tend to ____________________ electrons and form ____________________ ions. 15. Circle the letter of the statement that is true about ion size. a. Cations are always smaller than the neutral atoms from which they form. b. Anions are always smaller than the neutral atoms from which they form. c.
Within a period, a cation with a greater charge has a larger ionic radius.
d. Within a group, a cation with a higher atomic number has a smaller ionic radius. 16. Which ion has the larger ionic radius: Ca+2 or Cl- ? ________ Trends in Electronegativity (page 177) 17. What property of an element represents its tendency to attract electrons when it chemically combines with another element? _____________________________ 18. Use Table 6.2 on page 177. What trend do you see in the relative electronegativity values of elements within a group? Within a period? ___________________________________________________________ 19. Circle the letter of each statement that is true about electronegativity values. a. The electronegativity values of the transition elements are all zero. b. The element with the highest electronegativity value is sodium. c. Nonmetals have higher electronegativity values than metals. d. Electronegativity values can help predict the types of bonds atoms form. Summary of Trends (page 178) 20. Use Figure 6.22 on page 178. Circle the letter of each property for which aluminum has a higher value than silicon. a. first ionization energy
b. electronegativity
c. atomic radius
d. ionic radius and the
group 1A
Reading Skill Practice A graph can help you understand comparisons of data at a glance. Use the graph paper (in landscape orientation) on the next page to make a graph of the data in Table 6.2 on page 177. Plot electronegativity values on the vertical axis. Use a range from 0 to 4. Plot atomic number on the horizontal axis. Label each period and the first element in each period. 12
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Significance and Use of the Periodic Table DISCUSSION: When the Russian chemist, Dimitri Mendeleev, designed the first Periodic Table, he left blanks for elements he knew had not yet been discovered. His table was so accurate for the s and p electron columns that he was able to predict the properties of these elements. Since none of the atomic particles had been discovered by the 1860’s, he knew nothing about electron configurations, so he had to base his predictions solely on observable chemical and physical properties. We have looked at four trends in atomic properties — atomic and ionic radii, ionization energy, electronegativity, and electron affinity. In this “experiment,” you will play the role of a modern-day Mendeleev and predict some atomic and physical properties of four “unknown” elements from their location in the table.
Mendeleev Games PROCEDURE: Use the data contained in the periodic table on the next page to predict the properties of elements T, X, Y, and Z. 1. Base your predictions on the properties of neighboring elements and the apparent trends which occur across a period and down a group of the table. The properties which you will predict are shown below. atomic #
melting point symbol
electronegativity
I.E.
atomic radius
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Name _________________________________________________________________ Period _____________
periodic table of the representative elements of periods 2-6
CONCLUSION: Use the data provided in the table and your predictions to answer the following questions. 1. Write the definition for each of the following trends. Then write the general trend that occurs for the following properties across a period from left to right and down a group: a. electronegativity: _______________________________________________________________ ______________________________________________________________________________________ ______________________________________________________________________________________
b. atomic radius: _________________________________________________________________ ______________________________________________________________________________________ ______________________________________________________________________________________
c. ionization energy (I.E.): _________________________________________________________ ______________________________________________________________________________________ ______________________________________________________________________________________
2. Examine the melting point data. As one moves across a period, the melting point increases at first, and then decreases. Make a prediction as to why this occurs. _________________________________________________________________________________ ________________________________________________________________________________________
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According to the periodic table on the front of this page:
3. What element has the highest electronegativity? _______ Lowest electronegativity ________ 4. Complete the following charts for element T, X, Y, and Z.
Element T
Element X
symbol
symbol
name
name
predicted EN
predicted EN
shorthand SN
shorthand SN
common ion(s)
common ion(s)
formula of oxide compound (ionic bond)
formula of oxide compound (ionic bond)
Element Z
Element Y symbol
symbol
name
name
predicted atomic radius
predicted atomic radius
shorthand SN
shorthand SN
common ion(s)
common ion(s)
formula of oxide compound (ionic bond)
formula of hydrogen compound (ionic bond)
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NAME _____________________________________________________
PERIOD _________
Periodic Trends Online Tutorial DIRECTIONS: 1. Go to: http://www.wwnorton.com/web/chem1e/. Click on the picture 2. Near the top left hand corner of the page, click on “Choose a chapter.” Click on Chapter 8: Chemical bonding and atmospheric molecules 3. Scroll down to where it says, “Chapter 8 ChemTours” & choose “Periodic Table.” Answer the following questions 1. Why is the periodic table useful? _____________________________________________________________________ __________________________________________________________________________________________________ 2.
_______________________ developed the first periodic table. He used TWO criteria to organize the elements. What were they? _______________________________________________________________
3. The atomic number is the number of ________________________ in an element. 4. In a neutral atom, the number of _________ equals the ____________________ ___________________ 5. The mass of a sample of an element is the weighted ____________ of the different mass values of its isotopes. 6. The periodic table is divided into several vertical columns called ______________________, in which the elements have similar ________________________ _______________________. 7. By moving your mouse over several of the red group numbers, name and describe 6 groups on the PT. a.
______________________________________________________________________________________________ ______________________________________________________________________________________________
b.
______________________________________________________________________________________________ ______________________________________________________________________________________________
c.
______________________________________________________________________________________________ ______________________________________________________________________________________________
d.
______________________________________________________________________________________________ ______________________________________________________________________________________________
e.
______________________________________________________________________________________________ ______________________________________________________________________________________________
f.
______________________________________________________________________________________________ ______________________________________________________________________________________________
8. The horizontal rows on the periodic table are called _______________________. 9. The period number of each row corresponds to the _____________________ ______________________. 10. Name the two series or periods that appear at the bottom of the periodic table. The ______________________
____________________, which is part of period _____________.
The ______________________
____________________ , which is part of period ____________. 19
11. Describe a metalloid? ______________________________________________________________________________ __________________________________________________________________________________________________ 12. Define electronegativity. ___________________________________________________________________________ __________________________________________________________________________________________________ 13. What Nobel Prize winner developed the electronegativity scale? __________________ ________________ 14. What is the highest electronegativiy that an element can have? ______________ 15. What is the trend in electronegativity on the periodic table? ____________________________________________ __________________________________________________________________________________________________ 16. Define atomic radius. _______________________________________________________________________________ __________________________________________________________________________________________________ 17. What is the trend in atomic radius on the periodic table? ________________________________________________ __________________________________________________________________________________________________ 18. Arrange the following elements – Pr, Ag, Ra, F, Ge – in order of a.) increasing atomic radius
____________________________________
b.) increasing electronegativity
____________________________________
THE FOLLOWING QUESTIONS ARE #1-4 ON THE TUTORIAL 1. Which element has the following ground state electron configuration? 5
2
a.) [Kr]4d 5s ________
10
2
4
b.) [Ar]3d 4s 4p ________
1
c.) [Xe]6s ________
2
2
3
d.) 1s 2s 2p ________
2. Answer the question and sketch your answer on the periodic tables below. Increasing Electronegativity
Increasing Atomic Radius
Based on the trends of the periodic table, circle the element below that you would expect to have the greatest electronegativity. 3.
a.
Sb
b.
Br
c.
As
3.
a.
Ca
b.
Sr
c.
Ba
Based on the trends of the periodic table, circle the element below that you would expect to have the greatest atomic radius. 4.
a.
Ag
b.
Cu
c.
Au
4.
a.
Rb
b.
Zr
c.
Sn 20
Periodic Trends Review 1. Finish the following sentences with, “increases,” or “decreases.” a. As one moves from left to right across a period, the atomic size ___________________. b. As one moves from top to bottom in a group, the atomic size ____________________. c. As one moves from left to right across a period, the electronegativity ______________. d. As one moves from top to bottom in a group, the electronegativity ________________. e. As one moves from left to right across a period, the ionization energy ______________. f. As one moves from top to bottom in a group, the ionization energy _______________. 2. In each of the following sets of elements, which element has the smallest atomic size? a. Na, K, Rb ___________
e. Ba, Ca, Ra ___________
b. Na, Si, S
___________
f. P, Si, Al
c. N, P, As
___________
g. Rb, Cs, K ___________
d. N, O, F
___________
h. Cu, Ge, Bi ___________
___________
3. Arrange the following sets of elements in order of increasing atomic size. a. Sn, Xe, Rb, Sr
____________________________________________
b. Rn, He, Xe, Kr
____________________________________________
c. Pb, Ba, Ca, At
____________________________________________
4. In each of the following sets of elements, which element has the largest electronegativity? a. Na, K, Rb ___________
d. Ba, Ca, Ra ___________
b. Na, Si, S
___________
e. P, Si, Al
c. F, Cl, Br
___________
f. Zn, Ag, Pt ___________
___________
5. In each of the following sets of elements, which element has the smallest ionization energy? a. N, P, As
___________
d. Rb, Cs, K
___________
b. N, O, F
___________
e. Cu, Ge, Br ___________
c. Fr, Sr, V
___________
f. Sn, As, S
___________ 21
Factors affecting periodic trends Factor Nuclear Charge
Definition
Effect As the nuclear charge _______ across a period, the attraction between the protons & outermost electrons _______, thus causing……
Result Atomic size _____ Ionization E ____
Down a group, as the
Atomic Size
Shielding Effect
Electron Configuration
outer electrons get further from the nucleus (more energy levels), the electrostatic attraction _______, thus causing……
As the number of inner shell electrons __________ down a group, the electrostatic attraction_______, thus causing…..
Filled and half-filled sublevels are more _________________, thus causing…..
Atomic size _____ Ionization E ____
Atomic size _____ Ionization E ____
Exceptions to some trends
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Investigating the periodic trends among the elements
It’s Elementary – March Madness
INTRODUCTION:
March Madness is upon us! Every sports fan around the nation completes a bracket and tries their best to predict the winners and losers for each round of the national basketball championship. Creating the brackets, however, has a so-called scientific foundation called "bracketology." The NCAA Selection Committee uses this method to seed the field by ranking all teams from first through sixty-eight. In this lab you will apply the principles of bracketology to the properties of the elements. The competition among the 64 elements is stiff, and there is a wealth of information to research. Good luck and enjoy this, “elementary" version of March Madness. REVIEW OF ELEMENT PROPERTIES: Use your book (pages 170 - 178) and/or prior knowledge to define each of the following properties of the elements and describe any periodic trend in the property across a period or down a group. 1. Electronegativity a. Definition - _________________________________________________________________________ ______________________________________________________________________________________ b. Periodic Trend - _____________________________________________________________________ ______________________________________________________________________________________ 2. Atomic Radius a. Definition - _________________________________________________________________________ ______________________________________________________________________________________ b. Periodic Trend - _____________________________________________________________________ ______________________________________________________________________________________ 3. Ionization Energy a. Definition - _________________________________________________________________________ ______________________________________________________________________________________ b. Periodic Trend - _____________________________________________________________________ ______________________________________________________________________________________
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SUMMARY OF PERIODIC TRENDS: Fill in the lines with the appropriate periodic trend (electronegativity, atomic radius, or ionization energy) from page 1. NOTE: Pay close attention to the direction of the arrows. You are not filling in the periodic table with element symbols. DETERMINE WHICH TRENDS DECREASE & INCREASE AS ONE MOVES UP THE PERIODIC TABLE AND TO THE RIGHT.
______________________________________________________INCREASES
______________________________________________________INCREASES
______________________________________________________DECREASES
______________________________________________________DECREASES ______________________________________________________INCREASES ______________________________________________________INCREASES
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It’s Elementary – March Madness
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CONCLUSION: Answer the following questions. 1. Which element won "Elemental March Madness?"
_______________________________
2. Write its shorthand spectroscopic notation.
_______________________________
3. Draw its Lewis Structure.
_______________________________
4. Predict all stable ions that the atom can form.
_______________________________
5. Draw the Lewis Dot Structure for the ion(s).
_______________________________
6. Go to the website: http://www.chemicool.com/ Use the periodic table to research the champion and answer the following questions: a. List five common uses
b. For each of the champion’s opponents compare the actual atomic radii, electronegativity (EN), and first ionization energy. Was your prediction correct?
Atomic Radii Round
EN Round
1st IE ROUND
Champion
Opponent
Prediction Correct? (Y or N)
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Periodicity Review
Ion Formation Review Ions are formed by the _________________________ of electrons between atoms. Metals _____________________ e- to form ________________________. Nonmetals _________________________ e- to form ________________________.
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Ionic Size When metals ______________________ electrons they become _________________. When nonmetals __________________ electrons they become _________________.
So…… cations are always ________________________ than the atom. antion are always _______________________ than the atom.
Atom vs. Cation
Atom vs. Anion
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Examples: 1. Circle the particle in each pair that has the larger radius. a. K, K+
c. O, O-2
b. Br, Br -
d. Sb, Sb+3
2. In each pair, circle the larger ion: a. Sr+2 , Be+2
c. Te-2 , I-1
b. Fe+2 , Fe+3
d. Cs+1 , Tl+3
3. Which of the following atoms increase in size when they become ions? Cs, I, Zn, O, Sr, Al
4. List the following ions in order of increasing ionic radius: Na+ , Cl- , S-2 , F-1 , Al+3 , Se-2 __________________________________________________________
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Atomic Size Decreases Electronegativity Increases
Ionization Energy Increases
Electronegativity Increases
Atomic Size Decreases
Ionization Energy Increases
Size of cations decreases
Size of anions decreases
Atom vs. Ion *Positive ion is always SMALLER than the atom (ex: Ca+2 is smaller than Ca)* *Negative ion is always BIGGER than the atom (ex: S-2 is larger than S)* 30
Atomic Size Definition: the approximate size of an atom’s electron cloud Trend Across a Period: As the pull of the nucleus on the outer electrons increases, the size of the atom decreases. Trend Down a Group: As the number of energy levels increases, the size of the atom also increases.
Positive Ion Size Definition: the approximate size of an cation’s electron cloud
General Trend: When forming cations, electrons are removed but the nuclear charge remains the same. Therefore, positive ions are always smaller than their corresponding atoms. Trend Across a Period: As the pull of the nucleus on the remaining outer electrons increases, the size of the ion decreases Trend Down a Group: As the number of energy levels increases, the size of the cation also
increases.
Negative Ion Size Definition: the approximate size of an anion’s electron cloud
General Trend: When forming anions, electrons are gained but the nuclear charge remains the same. Therefore, because of the overabundance of electrons which repel one another, negative ions are always larger than their corresponding atoms. Trend Across a Period: As the pull of the nucleus on the outer electrons decreases, the size of the ion decreases. Trend Down a Group: As the number of energy levels increases, the size of the anions also
increases.
Electronegativity Definition: the measure of the ability of an atom to attract electrons to itself in a covalent bond. EN is a rating system, not a measurement.
Trend Across a Period: As the pull of the nucleus on the outer electrons increases, the electronegativity increases. Trend Down a Group: As the number of energy levels increases, the electronegativity decreases.
Ionization Energy Definition: the quantity of energy required to remove one electron from an atom; high IE indicates that it is difficult to remove an electron
Trend Across a Period: As the pull of the nucleus on the outer electrons increases, the ionization energy of the atom increases (harder to remove) Trend Down a Group: As the number of energy levels increases, which increases the shielding effect, the ionization energy of the atom decreases (easier to remove an electron). 31
Name ____________________________________________________ Period ___________________
THE PERIODIC TABLE - Vocabulary Review Match the correct vocabulary term to each numbered statement. Write the letter of the correct term on the line. Each answer can only be used once. a. representative elements b. electronegativity c. atomic radius d. metals e. cation f. nuclear charge g. transition elements ___________ 1. ___________ 2. ___________ 3. ___________ 4. ___________ 5. ___________ 6. ___________ 7. ___________ 8. ___________ 9. __________10.
__________11. __________12. __________13. __________14. __________15. __________16. __________17. __________18. __________19. __________20. __________21.
h. ionization energy i. transuranium elements j. alkali metals k. inner transition metals l. alkaline earth metals m. shielding effect n. period
o. ionic radius p. ion q. anion r. halogens s. nonmetals t. noble gases u. group
Elements found in groups 1A – 8A. Most of their highest occupied s and p sublevels are partially filled. Group B metals in which the highest s sublevel and a nearby d sublevel generally contain electrons. Elements in group IIA that have only 2 e- in the highest occupied E level. One half the distance between the nuclei of two atoms of the same element when the atoms are joined. The approximate size of a cation’s or anion’s electron cloud. The measure of the ability of an atom to attract electrons to itself in a covalent bond; a rating system, not a measurement. An atom or group of atoms that has a positive or negative charge. Elements in group 8A, in which the highest occupied s and p sublevels are filled. Nonmetals of group 7A. Elements in which the highest s sublevel and a nearby f sublevel generally contain electrons; an element in the lanthanide or actinide series; also called rare earth elements The quantity of energy required to remove one electron from an atom; high values indicates that it is difficult to remove an electron. A positively charged ion. Are always smaller than their atom. Group 1A elements, which have only 1 e- in the highest occupied E level. Good conductors of heat and electricity. They can be found on the left side of the staircase, center, and bottom of the periodic table. Poor conductors of heat and electricity. They can be found to the right side of the staircase. The number of p+ in the nucleus--it increases across a period. The inner shell e- shield the outermost e- from the pull of the nucleus. A negatively charged ion. Are always larger than their atom. Elements found after uranium on the periodic table. They are not found in nature, they are man-made. Horizontal row on the periodic table. Vertical column on the periodic table. 32
Name _________________________________
Periodically Puzzling Below are questions about the elements, their properties, and periodicity. In each case, the correct answer is one of the elements mentioned in the question. Write the answer in the appropriate space at the right, placing the first letter in the first blank. There are more than enough blanks to fit either name, so the number of letters in the name is not a clue. When the puzzle is completed, a very common statement about the Periodic Table will be revealed.
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44.
More outer electrons, phosphorus or silicon? Liquid at room temperature, cobalt or mercury? Produces a yellow flame, boron or sodium? Can be cut with a knife, dysprosium or chromium? Inner transition metal, cerium or polonium? Smaller atom, carbon or chromium? Higher ionization energy, krypton or potassium? Alkali metal, strontium or lithium? Can form +1 and -1 ion, hydrogen or bromine? Part of the Actinide series, samarium or einsteinium? 1 Configuration ends in 3p , aluminum or argon? Alkaline earth metal, barium or potassium? Part of the lanthanide series, Americium or Europium? 8 Configuration ends in 5d , platinum or palladium? Proverbial “lead balloon”, helium or xenon? Metal used in jewelry, sodium or rhodium? Isolated by Madam Curie, radium or rhenium? Its crystals sublime as violet gas, iodine or bromine? Most unreactive metal, copper or gold? One of the most dense metals, osmium or magnesium? Used to disinfect water, chlorine or bromine? Most electronegative element, francium or fluorine? Named after dynamite inventor, lawrencium or nobelium? Has a higher ionization energy, antimony or bismuth? Can exhibit a +3 charge, scandium or calcium? Larger atom, titanium or nitrogen? Reacts with water to produce H2, calcium or copper? Loses 3 electrons to form an ion, boron or nitrogen? Transuranium element, polonium or plutonium? Has the dot structure X., platinum or silver? Aqueous solutions are blue, copper or molybdenum? Lowest ionization energy, francium or fluorine? A poison, carbon or arsenic? Forms only a +2 ion, strontium or iron? A member of the noble gas family, radium or radon? A heavy metal poison, cadmium or aluminum? Reacts with O2 to form rust, iron or indium? Can exhibit more than one charge, cesium or cobalt? Its ion is smaller than its atom, nickel or nitrogen? A yellow element, selenium or sulfur? Member of period 6, fermium (#100) or holmium (#67)? Smaller electronegativity, rubidium or strontium? 1 14 5 Configuration is [Xe] 6s 4f 5d , rhenium or tungsten? Last naturally occurring element, uranium or nobelium?
1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. 42. 43. 44. PHRASE: ____________________________________________ ____________________________________________________ 33
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Name ____________________________________________________________
Period ________________
1. Why did Mendeleev leave spaces in his periodic table? ___________________________________________ ___________________________________________________________________________________________ 2. Identify each property below as more characteristic of a metal or a nonmetal. a) a gas at room temperature
____________________________________________
b) malleable
____________________________________________
c) poor conductor of electric current
____________________________________________
d) shiny
____________________________________________
3. In which group are the following located in the periodic table: a) alkali metals ______
b) halogens ______
c) alkaline earth metals ______
d) noble gases ______
4. Write the shorthand spectroscopic notation for the following elements: a) boron
____________________________________________
b) arsenic
____________________________________________
c) fluorine
____________________________________________
d) zinc
____________________________________________
e) aluminum
____________________________________________
5. Circle the element in each pair that has atoms with a larger atomic radius. a) sodium, lithium
b)
strontium, magnesium
c)
carbon, germanium
d)
selenium, oxygen
cesium, aluminum
d)
fluorine, bromine
I atom, I-1
d)
Al atom, Al+3
d)
ionic radius
6. Circle the element in each pair that has a greater ionization energy. a) lithium, boron
b)
magnesium, strontium
c)
7. Circle the particle in each pair that has the larger radius. a) Na atom, Na+
b)
S, S-2
c)
8. For which of these properties does lithium have a larger value than potassium? a) ionization Energy
b)
atomic radius
c)
electronegativity
9. Write the symbol of the element or elements that fit each description. a) A nonmetal in Group 4A
____________________________
b)
Inner transition metal with lowest atomic number
____________________________
c)
A metal in group 5A
____________________________
d)
All the nonmetals for which their atomic number is a multiple of 5
____________________________
10. In each pair, circle the larger ion: a.) Ca+2, Mg+2
b)
Cl-1, P-3
c)
Cu+1, Cu+2
d)
Si, Si-4
e)
Li+1, Rb+1 35
Standardized Test Prep 1)
Which of the following properties increase as you move across a period from left to right? I. electronegativity II. ionization energy III. atomic radius a) I and II only
2)
c)
II and III only
I, II, and III
b)
Cs, Na, S
c)
S, Na, Cs
b) ns2np5.
c)
a.
d)
Cs, S, Na
ns2np4.
d)
e)
Na, Cs, S
e)
ns2np1.
b.
If the pictures above represent the potassium atom and ion. __________
If the pictures above represent the sulfur atom and ion. a) Which sphere would most likely represent the atom? __________ The ion?
Use the data table to answer question 6
6)
III only
ns2np2.
a) Which sphere would most likely represent the atom? __________ The ion? 5)
e)
The electron configuration for an element in the halogen group should always end with a) ns2np6.
4)
d)
Which group has the symbols for sodium, sulfur, and cesium in order of increasing atomic radii. a) Na, S, Cs
3)
b) I and III only
Alkali Metal Li Na K Rb Cs
Atomic Radius 152 pm 186 pm 227 pm 244 pm 262 pm
__________
Ionization Energy (IE) 520 kJ/mol 495.8 kJ/mol 418.8 kJ/mol 250 kJ/mol 210 kJ/mol
Electronegativity Value (EN) 1.0 0.9 0.8 0.8 0.7
Is the relationship between the following properties inverse (I) or direct (D)? a) atomic radius and IE ______
b) atomic radius and EN ______
c) IE and EN ______
Each of the following questions are false. Explain why.
7) Electronegativity values are higher for metals than for nonmetals because atoms of nonmetals are among the largest atoms. ______________________________________________________________________ ____________________________________________________________________________________________ 8) A calcium atom is larger than a calcium ion because ions are always smaller than the atoms from which they are formed. ______________________________________________________________________________ _____________________________________________________________________________________________ 9) The element hydrogen is a metal because it is on the left in the periodic table. _________________________ ____________________________________________________________________________________________ 10) Among all the elements in a period, the noble gas always has the smallest ionization energy because within any period, atomic radii tend to decrease moving from right to left. __________________________ ___________________________________________________________________________________________
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The Periodic Law Pretest Choose the letter of the correct answer AND explain the reason for your answer in the spaces provided. ____________ 1.
According to the modern periodic law the properties of the elements are a periodic function of their a. ionic size. c. atomic mass. b. ionization energy. d. atomic number.
___________________________________________________________________________________________ ____________ 2.
Which of the following properties has a higher value for aluminum than silicon? a. Ionization energy c. Atomic size b. Electronegativity d. All of the above
____________________________________________________________________________________________ ____________ 3.
The electron configuration of an element ends with 4s1. Which of the following describes the element’s family? a. transition metal c. alkaline earth metal b. noble gas d. alkali metal
____________________________________________________________________________________________ ____________ 4.
The more an atom wants to lose an electron, the ___________ its ionization energy value is. a. higher c. none of the above. b. lower d. all of the above.
____________________________________________________________________________________________ ____________ 5.
Neutral atoms with an s2p6 end notation would be classified as a a. noble gas. c. transition metal. b. halogen. d. alkali metal.
____________________________________________________________________________________________ ____________ 6.
Elements in a group have similar chemical properties because of similar a. nuclear structure. c. principal quantum number. b. outer electron configuration. d. mass number.
____________________________________________________________________________________________ ____________ 7.
The energy required to remove an electron from an atom is the atom’s a. electron affinity. c. electronegativity. b. electron energy. d. ionization energy.
____________________________________________________________________________________________
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____________ 8.
The electron configuration of a potassium ion, K+, matches that of an atom of a. argon. c. sodium. b. calcium. d. krypton.
____________________________________________________________________________________________ ____________ 9.
The electronegativity value of Mg is ______ than Al’s. a. greater c. less b. the same as d. none of the above.
____________________________________________________________________________________________ ____________ 10.
Which of the following has the largest electronegativity? a. cesium c. arsenic b. sodium d. chlorine
____________________________________________________________________________________________
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The Periodic Law Practice Test Choose the best answer. 1. What two properties did Mendeleev use to organize his Periodic Table? a. Chemical properties and atomic mass. c. Periodic trends and atomic number. b. Periodic trends and number of protons. d. Similar electron configurations and atomic mass. 2. Moseley developed the first Periodic Table based on atomic a. mass. c. size. b. weight. d. number. 3. According to modern periodic law the properties of the elements are periodic functions of their a. ionization energy. c. ionic size. b. atomic mass. d. atomic number. 4. The more an atom wants to lose an electron, the ___________ its ionization energy value is. a. higher c. none of the above. b. lower d. all of the above. 5. Neutral atoms with an s2p6 end notation would be classified as a a. noble gas. c. transition metal. b. halogen. d. alkali metal. 6. Elements in a group have similar chemical properties because of similar a. nuclear structure. c. principal quantum number. b. outer electron configuration. d. mass number 7. Which of the following statements is true? a. The size of a cation is larger than the size of its neutral atom b. The size of a cation is smaller than the size of its neutral atom. c. The size of an anion is smaller than the size of its neutral atom. d. None of the above. 8. The electron configuration of a rubidium ion, Rb+, matches that of an atom of a. He c. Ar b. Ne d. Kr 9. Which of the following is listed in order of decreasing electronegativity? a. chromium, carbon, cobalt c. carbon, cobalt, chromium b. chromium, cobalt, carbon d. None of the above. 10. Which of the following has the largest electronegativity? a. potassium c. astatine b. sodium d. bromine 11. Which of the following properties decreases as you move across a period from left to right? I. Electronegativity II. Ionization energy III. Atomic size a. I only. c. I and II only. b. III only. d. I, II, and III.
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True or False. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.
Among all the elements in a period, the noble gas always has the largest ionization energy. _______ It is more difficult to remove an electron from strontium than beryllium. _______ Francium is the most electronegative element. _______ The barium atom is smaller than the barium ion. _______ The P-3 ion is smaller than the P atom. _______ The noble gases are the most reactive nonmetals. _______ Electronegativity values are lower for metals than for nonmetals. _______ Atomic radius and electronegativity have similar trends. _______ Atoms and moles are conserved in a chemical reaction. _______ Aluminum is a metalloid. _______ The alkali metals are the most reactive metals on the periodic table. _______
Cumulative Review 23. How many significant figures are in the measurement 0.000456 grams? a. 2 c. 6 b. 7 d. 3 24. How many formula units are contained in one mole of calcium chloride? a. 6 c. 6.02 x 1023 b. 111 d. 3.6 x 1024 25. Pick the best term to describe a banana split. a. heterogeneous mixture b. compound
c. element d. solution
26. The products of a complete combustion reaction are a. carbon monoxide and water. c. oxygen and hydrogen. b. carbon dioxide and water. d. oxygen and water. 27. What are the most common ions formed by the lead atom? a. -2, -4 c. +2, +3 b. +1, +2 d. +2, +4 28. The presence of hydroxide in a chemical formula indicates that the compound is a(n) a. base. c. hydrate. b. acid. d. salt. 29. The formula for ammonia is ______. a. NH4 b. NH2
c. NH3 d. NH4+1
30. An element in the ‘f’ block of elements would best be described as(n) a. transition metal. c. inner transition metal. b. noble gas. d. halogen. 31. An element that is a poor conductor of heat and electricity is a. sulfur. c. gold. b. copper. d. titanium. 32. The most common type of ion formed by Group IIIA is a(n) a. cation b. anion
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Periodic Law Prelab In this lab we are going to use water displacement to calculate the volume of a metal sample. To do this properly, we need to determine the best instruments to use by being aware of the error that can evolve from measurements. Determine the calibration and estimated column of the following graduated cylinders. Then read the instruments and place the answer in the space provided. Cal ___________________
Cal ___________________
Est ___________________
Est ___________________
________________________
_______________________
The volume of the sample is _________________________________. The mass of the sample of copper is 0.22 g. The density of copper is __________________________.
How do you know that this answer cannot be correct? ___________________________________. What changes to your technique would eliminate this error in your result? ____________________________________________________________________________________
Let’s use another student’s volume measurement. Volume __________________________
Density ___________________________
Should the answers at least be close to each other? _______________ Are they? ______________
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Let’s do the same thing, only this time we will use a larger sample that weighs one hundred times the first sample – 22 g and a different graduated cylinder.
_______________________
_______________________
The volume of the sample is _________________________________. The density of copper is __________________________.
Does this seem more plausible than the first result? ___________________________________. Compare your answer to another student who has a different volume. Are your results more similar than the first trial? _____________________________________________________________
This exercise should show you the importance of using the appropriate size sample for the equipment you choose. Remember to read the instruments properly and make sure your answers make sense! 42
The Periodic Law
Examination of some periodic properties of the elements INTRODUCTION: When the elements are arranged in order of increasing atomic number, there is a periodic recurrence of properties that leads to the grouping of elements in the periodic table. Elements in vertical columns form groups or families that are characterized by marked similarities in physical and chemical properties. These similarities are due, in large part, to the fact that all the elements within a group have the same outer-shell electron configuration. H. G. J. Moseley formulated this trend into the Law of Chemical Periodicity. Within a group, periodic trends of certain properties can be observed. The properties of density and solubility of compounds, for example, are known to vary regularly within groups of elements. In this experiment, you will investigate the periodic variation of density and solubility of compounds within groups. Specifically, you will determine the densities of certain elements in Group IVA and the solubilities of certain salts of Group IIA elements. You will then use your results to make predictions of the densities of other Group IVA elements and the general trend that exists among the solubilities of alkaline earth metal ions.
1. 2.
3.
4. 5.
OBJECTIVES: To examine the periodic variation of the density and solubility of compounds within groups of elements. To make predictions of densities of untested Group IVA elements. MATERIALS: lead shot, Pb 0.1 M barium nitrate silicon, Si 0.1 M calcium nitrate tin, Sn 0.1 M magnesium nitrate test tube rack 0.1 M strontium nitrate distilled water 1 M sodium carbonate 4 small test tubes 1 M potassium chromate 0.25 M ammonium oxalate, (NH4)2C2O4 PROCEDURE: Part A. Densities of Group IVA Elements 1. Obtain dry samples of tin (1 piece), lead (a spoonful or two), and silicon (a few pieces). 2. Collect the data necessary to determine the densities of the tin, lead, and silicon samples by the water displacement method. The amount of sample and the equipment used is up to you, so be smart about it to obtain accurate results. 3. Place the wet samples in the properly labeled beakers on the center distribution table. DO NOT throw them away.
6. 7. 8.
Part B. Solubilities of Salts of Group IIA Elements Obtain four test tubes; clean them thoroughly with soap and water. Rinse with distilled water. To the first tube, add 1 mL ( roughly 20 drops) of Mg(NO3)2 solution. To the second tube, add 1 mL of Ca(NO3)2 solution. To the third tube, add 1 mL of Sr(NO3)2 solution, and to the fourth, 1 mL of Ba(NO3)2 solution. Note that these volume measurements need only be approximate as this procedure is qualitative. Add 1 mL of 1M potassium chromate solution to each test tube to provide the chromate ions for reaction with the Group IIA metal ions. If the metal chromate salt (MgCrO4, CaCrO4, SrCrO4, or BaCrO4) is insoluble in water, the solution will become cloudy and a thick precipitate will be formed upon addition of K2CrO4. If the salt is slightly insoluble in water, the solution will produce a few specs of solid. If the metal chromate salt is soluble in water, the solution will remain clear upon addition of K2CrO4. Record the solubility of each metal chromate salt as S (soluble), SI (slightly insoluble) or I (insoluble). Rinse the test tubes with distilled water; repeat step 2. Add 1 mL of 0.25 M ammonium oxalate, (NH4)2C2O4, to each test tube. Record your solubility results. Rinse the test tubes with distilled water; repeat step 2 again. Add 1 mL of 1M sodium carbonate to each test tube. Record your solubility results. Clean the test tubes; return them to their original location.
CONCLUSIONS: 1. Calculate the densities of the Si, Sn, and Pb samples. Record in Table 1. You do not need to show your work. Answer questions 2-5 below the tables. 2. Using a complete sentence, state a general trend in density for elements in the same group on the periodic table. 3. Predict the numeric densities of carbon and germanium. Explain your reasoning. 4. Using a complete sentence, state a general trend in solubility for the alkaline earth metals. 5. Predict the solubilities of the beryllium and radium salts. Explain your reasoning.
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Names ______________________________________________________________ Period _________
Table 1: Densities of Group IVA Elements Si
Sn
Pb
mass of metal volume of water volume of water & metal volume of metal density of metal
Table 2: Solubilities of Salts of Group IIA Elements CrO4-2
C2O4-2
CO3-2
Mg+2 Ca+2 Sr+2 Ba+2
2. _________________________________________________________________________________ _________________________________________________________________________________ 3. Density of C ______________________________ _________________________________________________________________________________ Density of Ge _____________________________ _________________________________________________________________________________ _________________________________________________________________________________ 4. _________________________________________________________________________________ 5. _________________________________________________________________________________ _________________________________________________________________________________
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WHAT dO I need to know?? Unit 10: The Periodic Table PART I: multiple choice o Dmitri Mendeleev (how did he organize his table? o Who was Moseley? How did he organize the PT? o State the modern periodic law o location of groups on the periodic table (i.e. alkali metals, alkaline earth metals, halogens, noble gases, etc.) o electron configurations o Definitions (ionization energy, electronegativity, atomic radius, period, family/group, cation, anion) o Ion size vs. atom size o Periodic trends: Atomic Radius Electronegativity Ionization Energy Ionic Radius PART II: True & False o o o o
periodic trends most electronegative element least electronegative element atom vs. ion size
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part III: cumulative review definition of atomic mass significant figures Avogadro’s number and the mole homogeneous vs. heterogeneous solution vs. mixture most wanted list (ammonia, methane, baking soda, chalk, road salt, etc.) o combustion reactions (incomplete vs. complete) o ion formation o formulas of acids vs. bases o o o o o o
PART Iv: periodic table puzzle o you will be given a set of clues and your job is to arrange the elements in the proper periodic order
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